*{
    box-sizing: border-box;
}
body {
    margin: 0;
    padding: 0;
    div{
        margin: 0 auto;
        width: 300px;
        height: 300px;
        text-align: center;
    }
    ul {
        position: relative;
        margin: 0;
        padding: 0;
        width: 100%;
        font-size: 0;
        li {
            display: inline-block;
            margin: -4px 0 0 -4px;
            border:4px solid #aaa;
            width: 100px;
            height: 100px;
            line-height: 100px;
            font-size: 1rem;
            text-align: center;
            cursor: pointer;
            &:hover{
                background: #eee;
            }
        }
    }
}
a{
    margin-top: 1em;
    display: inline-block;
    padding: .3em 1em;
    background: #428bca;
    text-decoration: none;
    color: #fff;
    font-family: courier;
}
